A number of research projects are concerned with the development of efficient heat storage systems – usually aimed at achieving a high level of economic efficiency. The Bio2Geo research project provides a new approach for a plant that is not only highly efficient, but also profitably combines various energy-generating technologies. One of the aspects the project will be investigating is the seasonal storage of surplus waste heat from biomass plants in near-surface geothermal probe fields; the stored energy can then be used in the winter months to cover the higher heating demand.

At the same time, the hybrid power plant to be developed is to use part of the unused heat to remove the contents and fermentation residues of the biogas plant. The conversion process allows the elimination of pollutants, such as pesticides and veterinary pharmaceuticals. This results in high-quality fermentation products and fertilizers that comply with current hygiene regulations and further improve the revenue situation of the biogas plant. The feasibility of the project is to be established with the demonstration plant, which the project partners from research and industry will present at the end of the project.

Simulations have shown that this way it is possible to increase the efficiency of the hybrid power plant, currently estimated to be at 70% with seasonal heat storage, to 83%.

The project is being funded by the Federal Ministry for Economic Affairs and Energy (BMWi) until the end of March 2021.